Extended-life pen

ABSTRACT

A pair of interchangeable pen units are disposed side-by-side within a barrel with a portion of each pen unit projecting beyond an end of the other pen unit, the pen units being linked together for transmitting writing thrust from the projecting portion of one pen unit to the writing tip of the other pen unit. The barrel may include a conventional mechanism to operate said linked pen units for selectively retracting or projecting said writing tip.

United States Patent 1191 1111 3,856,420

()ltmann Dec. 24, 1974 [54] EXTENDED-LIFE PEN 2,971,494 2/1961 Seyer 401 217 2,972,335 2/1961 Grube et al 401 217 [75] lnvemor- Fay 01mm, Anamosa Iowa 3,216,398 11/1965 Washcalus 401 217 [73] Assignee: souvenir/Incorporated, Cedar 3,801,206 4/1974 Poritz 401/29 Rapids, Iowa Filed: Ja 9 Primary ExaminerLawrence Charles [21] App]. No.: 435,881 [57] ABSTRACT A pair of interchangeable pen units are disposed side- [52] U.S. Cl 401/109, 401/29, 401/35, ywi hin a rr l wi h a porti n f each pen unit 401 /21() projecting beyond an end of the other pen unit, the [51] Int. Cl B4311 7/12, B431: 27/04 p n un ng linked t g th r f r transmitting writ- [58] Field ofSeareh ...401/29, 34, 217, 35, 109-1 14, ing thrust from the projecting portion of one pen unit 401 /209, 210, 292 to the writing tip of the other pen unit. The barrel may include a conventional mechanism to operate said [56] References Cited linked pen units for selectively retracting or projecting UNITED STATES PATENTS sald Wmmg 1 2,865,334 12/1958 Radzinsky 401/209 5 Claims, 9 Drawing Figures Patented Dec. 24, 1974 F/GJ H612 EXTENDED-LIFE PEN FIELD OF THE INVENTION This invention relates to writing instruments, and in particular to so-called retractable pens.

BACKGROUND OF THE INVENTION Various forms of pens are known that incorporate plural pen units. In one form, two pen units are disposed end-to-end so that the whole pen is at least equal in length to the combined lengths of the pen units. Plural pen or pencil units are also found in multicolor writing instruments, where one of several writing units can be selectively projected into writing position provided that all the others are shifted to their retracted positions. This latter construction is complex in that it involves a separate selective mechanism for each pen unit.

SUMMARY OF THE INVENTION Two pen units are disposed side-by-side with a portion of each projecting beyond an end of the other. The pen units are contained in a barrel that guides and exposes the writing tip of one pen unit, which may be called the active pen unit. The opposite end of the barrel is closed and applies writing thrust to the other pen unit which may be called the stored pen unit. Means links the pen units together so that the writing thrust applied to the stored pen unit is transmitted to the active pen unit and to its writing tip. The pen units may be interchanged either because the active pen unit has run out of fluid or (where the pen units are of different colors) to change writing color. In interchanging the pen units, the stored pen unit becomes active and the previously active pen unit becomes the stored unit.

Ideally, the pen units used are of a standard commercial form. This involves a long tube containing writing fluid and a short end portion of reduced diameter ending in a ball-point writing tip. The junction of the reduced-diameter portion and the tube forms a shoulder. At a minor part of the length of the tube away from the writing tip there are two lateral projections. (These pen units are used in retractable" pens, where one end of a coil compression spring abuts against the lateral projections while the opposite end of the spring acts on the barrel to bias the pen unit toward the retracted position.) In a specific aspect of the invention, the means which links the pen units together is a part having an opening through which the active pen unit extends, with the linking part bearing against the lateral projections. The stored pen unit bears on the linking part, thus providing for transmission of writing thrust to the active pen unit from the stored pen unit. Still more particularly, the linking part has a hole which receives the reduced-diameter portion of the stored pen unit, so that the shoulder bears against the linking part. The pen units may be interchanged at an appropriate time by the user, using the same linking part.

The assembled active and stored units are utilized in a retractable pen according to a further feature of the invention. In its presently preferred form, this involves use of the usual compression coil spring about the lower end of the active pen unit and utilizes a standardized type of project/retract mechanism at the top of the barrel, cooperating with the projecting portion of the stored pen unit.

The nature of the invention and its further novel features and their advantages may be better understood from the following description of the illustrative embodiment of the invention shown in the accompanying drawings. In the drawings:

FIG. 1 is a lateral view of a retractable pen constituting an illustrative embodiment of the invention;

FIG. 2 is a lateral view of the pen of FIG. 1, with portions of the barrel thereof broken away and other portions shown in cross-section;

FIG. 3 is an enlarged top plan view of a linking part in the retractable pen of FIG. 2 and, in phantom, the pen barrel;

FIG. 4 is a cross-section of the linking part viewed at the plane 44 of FIG. 3;

FIG. 5 is an enlarged longitudinal cross-section of the assembled movable parts of the selective retraction mechanism at the top of the pen in FIG. 2;

FIGS. 6 and 7 are transverse cross-sections of the assembled parts shown in FIG. 5 as viewed at the planes 6-6 and 77 respectively;

FIG. 8 is a transverse cross-section of the stationary part of the selective retraction mechanism as viewed at the plane 8-8 in FIG. 2; I

FIG. 9 is a greatly enlarged developed view, from the inside, of the stationary part of the selective retraction mechanism, including in phantom the cooperating parts of the mechanism of FIG. 5.

Referring now to the drawings, the illustrative pen includes first and second ball-point pen units 10 and 12, which may also be called active and stored pen units, in the assembled configuration. The pen units are interchangeable, so that the first pen unit would become stored and the second pen unit would become active. These pen units are of a widely known conventional form, each having an elongated tube 14, a pair of diametrically opposite lateral projections 16, and a ball-point writing tip 20. An end portion 22 of each pen unit, commonly of metal, is secured to tube 14, and end part 22 is of reduced diameter for most of its exposed length compared to the diameter of tube 14. The junction of the reduced-diameter length 22 with the restof the pen unit forms a shoulder 24.

A linking part 26 contains two openings, bores 28 and 30 which receive tube 14 of pen unit 10 and reduced-diameter length 22 of pen unit 12, respectively. The bore sizes are limited so that shoulder 24 of stored pen unit 12 bears on linking part 26, and linking part 26 bears on lateral projections 16 of active pen unit 10.

The assembled pen units and their linking part are contained in barrel means which includes an elongated barrel 32 that is tapered toward its lower end and at its lower end it includes a portion 32a having a through passage which guides the lower end portion of the active pen unit and exposes the writing tip 20, in the illustrated condition of the parts. The barrel means includes a tight-fitting but removable top unit 32b whose function is to apply writing thrust from the barrel to the stored pen unit 14 to the active pen unit 10 via linking part 26.

As thus far described, the pen represents a useful improvement, enabling the user to keep in reserve a spare" pen unit or a pen unit having writing fluid of a color different from that in the active pen unit. The stored pen unit may be made active by removing top unit 32b and reassembling the parts with the pen units in interchanged positions.

As an important added feature of the invention, the assembled pen units function as one combined pen unit with top unit 32b formed as a wholly conventional mechanism to provide selective retraction of the writing tip. The length of the combined pen unit is only moderately greater than the length of the usual retractable pen itself. The increase in length is less than the part of each pen unit between its writing tip and its lateral projections 16. Various mechanisms are useful for this purpose and are well known. However, to be sure of providing a complete description of the illustrative embodiment, the preferred mechanism will be described briefly.

FIGS. -9 show details of the preferred selective retraction mechanism. That mechanism includes a movable assembly including an actuator 34 the top of which has a metal-cup cover 36 and an interposer 38. The movable assembly works within fixed member 40. Parts 34, 36, 38 and 40 together constitute the top unit 32b of the barrel unit.

Fixed member 40 has three relatively deep grooves 42 and three relatively shallow grooves 44 parallel to the axis of member 40. The deep and shallow grooves alternate around the axis, spaced at 60 intervals. The deep grooves receive three radially large splines 46 of member 38. The shallow and deep grooves receive all six radially small splines 48 of actuator 34. The upper edges 46a of splines 46 slant. Below the ribs 50, which define grooves 42 and 44, member 38 has a cylindrical surface 52 whose diameter is slightly larger than that of splines 46. The lower ends of ribs 50 slant so as to be complementary to slant surfaces 46a. Slant-surfaces 54 at the lower ends of shallow grooves 44 (within the large-diameter surface 54) extend the slant surfaces 50a of alternate splines 50.

A compression coil spring 56 (FIG. 2) receives the lower portion of pen unit 10. The lower end of spring 56 abuts against a shoulder 58 in barrel 32 and the upper end of spring 56 abuts against lateral projections 16 of the active pen unit. In this way, spring 56 biases the pen units and 12 upward. The top of stored pen unit 12 is received in bore 60 in interposer 38 and is pressed against the upper end of that bore. interposer 38 is thus biased against actuator 34, and the slant edges 46a (FIG. 9) are biased against slant surfaces 54 of stationary member 40 in the illustrated condition of the assembled pen units, where the writing tip of active pen unit 10 projects from the barrel 32. In this way the writing thrust of the user applied to barrel 32 is transmitted via parts 40, 38, 12 and linking member 26 to active pen unit 10.

Actuator 34 has a series of sloping surfaces 48a at the ends of splines 48. When actuator 34 is depressed, those surfaces 48a drive interposer 38 downward. When splines 46 move below the tips of ribs 50, the bias provided by spring 56 causes interposer 38 to be indexed. This occurs initially because of the coaction of slant surfaces 46a with slant surfaces 48a of actuator 34, and then because of the coaction of slant surfaces 460 of the interposer with stationary slant surfaces 50a. As a result, splines 46 enter deep grooves 42, allowing the actuator assembly 34, 38 and the pen-unit assembly 10, 12, 26 to shift upward when downward pressure on actuator 34 is relaxed, retracting the writing tip within the barrel. Subsequent depression and release of actuator 34 similarly causes 60 indexing of interposer 38 to assume the configuration of FIG. 9 with the writing tip 20 projecting from the barrel.

Various changes in the illustrated embodiment are readily envisioned. For example, hole 30 in linking member 26 might be omitted and then the writing tip 20 of stored pen 12 would bear on member 26. This is within the broad concepts of the invention, but it has disadvantages. Thus, it would apply possibly harmful stress to the reduced-diameter length 22, and it would needlessly increase the required length of barrel 32. As another alternative, pen unit 12 could be inverted and it could be permanently linked or united to pen unit 10. While that arrangement would make it easier for the user to interchange the active and stored pen units, it has the disadvantage of holding the stored pen unit 12 with its writing tip uppermost when active pen unit 10 is in use. In such an inverted condition there is danger of the stored pen unit becoming inoperative. Still other configurations and varied application of the novel features of the invention will occur to those skilled in the art. Consequently, the invention should be construed broadly in accordance with its full spirit and scope.

What is claimed is:

1. An extended-life pen, including first and second elongated pen units disposed side by side with a segment of each of said pen units projecting beyond an end of the other of said pen units, each of said pen units having a writing tip, barrel means containing said pen units and having guiding passage means at one end thereof for exposing the writing tip of said first pen unit and having means at the opposite end thereof for applying writing thrust to the projecting end portion of said second pen unit, and means linking said pen units together for transmitting said writing thrust from said second pen unit to said first pen unit, said first and second pen units being interchangeable for disposing the writing tip of the second pen unit in said guiding passage and for utilizing the first pen unit to transmit writing thrust from said barrel means to said second pen unit.

2. An extended-life pen in accordance with claim 1, wherein most of the length of each of said pen units comprises a tube having a lateral enlargement spaced from both ends thereof, and wherein said linking means comprises a part having an opening through which said first pen unit extends, an end portion of said second pen unit bearing against a portion of said linking part, the lateral enlargement of the first pen unit forming an abutment on which the linking part bears for transmitting writing thrust from the second pen unit to the first pen unit.

3. An extended-life pen in accordance with claim 2, wherein the end portion of each pen unit adjacent its writing tip comprises a relatively short length of reduced diameter, compared with the diameter of said tube, each pen unit thus having a shoulder defined by the junction of said reduced-diameter length with the rest of the pen unit, and wherein said linking part is formed to include an aperture that receives the reduced-diameter length of said second pen unit, said shoulder of said second pen unit bearing on said linking part.

4. An extended-life pen in accordance with claim 1, wherein said barrel means includes a mechanism cooperating with said second pen unit for causing said writing tip of said first pen unit to project to an exposed position or, selectively, to allow retraction thereof into said barrel means, further including a coil compression of said second pen unit, said shoulder of said second pen unit bearing on said linking part, and wherein said extended-life pen further includes a mechanism cooperating with said second pen unit for causing said writing tip of said first pen unit to project to an exposed position or, selectively, to allow retraction thereof into said barrel means, further including a coil compression spring confined endwise between said lateral enlargement of said first pen unit and said barrel means for biasing both of said pen units toward said mechanism. 

1. An extended-life pen, including first and second elongated pen units disposed side by side with a segment of each of said pen units projecting beyond an end of the other of said pen units, each of said pen units having a writing tip, barrel means containing said pen units and having guiding passage means at one end thereof for exposing the writing tip of said first pen unit and having means at the opposite end thereof for applying writing thrust to the projecting end portion of said second pen unit, and means linking said pen units together for transmitting said writing thrust from said second pen unit to said first pen unit, said first and second pen units being interchangeable for disposing the writing tip of the second pen unit in said guiding passage and for utilizing the first pen unit to transmit writing thrust from said barrel means to said second pen unit.
 2. An extended-life pen in accordance with claim 1, wherein most of the length of each of said pen units comprises a tube having a lateral enlargement spaced from both ends thereof, and wherein said linking means comprises a part having an opening through which said first pen unit extends, an end portion of said second pen unit bearing against a portion of said linking part, the lateral enlargement of the first pen unit forming an abutment on which the linking part bears for transmitting writing thrust from the second pen unit to the first pen unit.
 3. An extended-life pen in accordance with claim 2, wherein the end portion of each pen unit adjacent its writing tip comprises a relatively short length of reduced diameter, compared with the diameter of said tube, each pen unit thus having a shoulder defined by the junction of said reduced-diameter length with the rest of the pen unit, and wherein said linking part is formed to include an aperture that receives the reduced-diameter length of said second pen unit, said shoulder of said second pen unit bearing on said linking part.
 4. An extended-life pen in accordance with claim 1, wherein said barrel means includes a mechanism cooperating with said second pen unit for causing said writing tip of said first pen unit to project to an exposed position or, selectively, to allow retraction thereof into said barrel means, further including a coil compression spring confined endwise between a portion of said first pen unit and said barrel means for biasing both of said pen units toward said mechanism.
 5. An extended-life pen in accordance with claim 2, wherein the end portion of each pen unit adjacent its writing tip comprises a relatively short length of reduced diameter extending from said tube, each pen unit thus having a shoulder defined by the junction of said reduced-diameter length with the rest of said pen unit, and wherein said linking part is formed to include an aperture that receives the reduced-diameter length of said second pen unit, said shoulder of said second pen unit bearing on said linking part, and wherein said extended-life pen further includes a mechanism cooperating with said second pen unit for causing said writing tip of said first pen unit to project to an exposed position or, selectively, to allow retraction thereof into said barrel means, further including a coil compression spring confined endwise between said lateral enlargement of said first pen unit and said barrel means for biasing both of said pen units toward said mechanism. 